1. Field of the Invention
The invention pertains to a fuel filler system in an automotive vehicle and more specifically to a safety structure shielding the sealing cap at the end of the fuel filler tube or hose from contact with nearby portions of the vehicle body in cases of vehicle collision or other serious vehicle body deformation.
2. Brief Description of the Prior Art
Recent developments in automotive safety have included attempts to minimize the danger to passengers and the damage to the vehicle in cases of traffic accidents. An important consideration in this regard is the possibility of fire due to fuel leakage. The fuel filler tube or hose leading from the gas or fuel cap to the fuel tank is preferably a cause of fuel leakage as its length makes it vulnerable to vehicle body damage.
Recently developed structures can adequately protect the point of connection between the filler tube and the fuel tank. As will be described in detail later, mating flanges on the fuel tank and the lower end of the filler tube can be secured by bolts and sealed with an O-ring or the like to form a strong and fluid-proof junction resistant to deformation in any direction. However, the upper end of the filler tube can only be sealed with a removable gas cap and can only be attached to a relatively weak outer body panel. Thus, in cases of severe body deformation, the sealing cap may be damaged.
Some attempts have already been made to remedy the situation. For example, a gas cap described in U.S. Pat. No. 4,142,756 to Henning et al comprises a handle loosely attached to a portion which mates with threads in a filler tube. If the handle is subjected to excessive forces, it breaks away, leaving the other portion in sealing contact with the filler tube. This arrangement also features a protective collar interposed between the sealing ring of the gas cap and the nearest part of the vehicle body to prevent direct contact therebetween in cases of body deformation.
While improving vehicle safety, this structure does have the drawback of allowing the gas cap assembly to be easily damaged. That is, when the handle separates as designed, it leaves the other portion lodged within the filler tube, necessitating troublesome removal and unnecessarily expensive replacement.